简介：Miaowan()ophiolite是在Yangtzecraton的北边缘附近外面收割的高度割下的ophiolitic建筑群。这建筑群的岩石由组成，从底部到顶，局部地包含podiform铬铁矿的harzburgitetectonite，纯橄榄岩，分层、各向同性的斑粝岩，sheeted堤建筑群(SDC)，有燧石豆荚和层的元枕头熔岩，和构造地设置的大理石。SDC向下是Miaowanophiolitic顺序，和等级的很重要、重要的部分进斑粝岩和ultramafic岩石，并且进元枕头熔岩向上。一些堤保存单程的chilled边缘，典型地代表extensionalophiolitic背景而大多数保存两倍chilled边缘，在寒心的方向能的情况中决定了。SDC主要由元辉绿岩(粗玄岩)组成，元斑粝岩和ultramafic的meta-plagiogranite，和小数量摇。LA-ICP-MS锆石标明日期收益一上面拦截年龄1026?????????????????????慩睯湡??灯楨汯瑩??丠潥牰瑯牥穯楯??慵杮楬杮？

简介：EarlyPaleozoicgranodioritehasbeenidentifiedonthenorthernmarginoftheNorthChinacratonintheeastsectionofthecentral-Asianorogenicbelt,whichwaspreviouslyknownasearlyIndosinianinage.ByusingtheLA-ICP-MSmethod,theobtainedzirconU-Pbageis445.62.7Ma,whichrepresentsthecrystallizationageofthegranodiorite.Thegranodioriteneartheeastofthelarge-sizedBilihegolddepositisofthetholeiiteserieswithlowpotassium.Itisquasi-aluminousI-typegranite,enrichedinsodium(Na2O/K2O=7.299.77)andmagnesium(Mg#=0.510.67).TheΣREEvalueisrelativelylow,obviousdifferentiationisshownbetweenLREEandHREEandwithinLREE,andtheEuanomalyislowandnegative(δEu=0.740.91).Intheprimitive-mantlenormalizedspiderdiagramsoftraceelements,thegranodioriteisrelativelyrichinLREEandLILE(Ba,Sr,Th),andstronglydepletedinHFSE(Nb,Ta,TiandP),whichshowsfeaturesofsubductionzonecomponents(SZC).InthediscriminationdiagramsoftectonicsettingsofgraniteforRbvs.(Nb+Y),Rbvs.(Ya+Ta),La/Nbvs.Ba/NbandTh/Nbvs.Ba/Nb,thegranodioriteexhibitstypicalfeaturesofislandarcgranite.ThenormalizedvaluesofKandRbareextremelylow,whilethevaluesofSrandEuareveryhigh,whicharesimilartothoseofislandarcmagmathathasundergonemetasomatismoffluidfromtheoceaniccrust.ThegranodioriteisrelativelydepletedinεHf(t)(5.17.1)andlowinεHf(t)modelages(1089921Ma).IntheεHf(t)vs.age(T)diagram,thedistributionareaofthegranodioriteisaccordantwiththefieldoftheXing'anling-Mongoliaorogenicbelt,whichindicatesthatthemagmaticsourcesaremainlythemixtureofpartialmeltingofwedgedmantlesubjectedtometasomatismoffluidfromtheoceaniccrustandyoungsubstancefromthecrust.ThegranodioriteissimilartothefelsicarcmagmaintheDamaoBanner,BateObon,BoinSumandOrdorSumregions,andtheyaltogetherconstituteanearlyPaleozoicaccretionaryislandarcma